JP5680675B2 - Blood processing filter and method for priming blood processing filter - Google Patents

Description

  The present invention relates to a blood treatment filter for removing undesirable components such as aggregates and leukocytes from blood. Precise and disposable blood treatment filters and blood treatments used for the purpose of removing microaggregates and leukocytes that cause side effects from whole blood preparations, red blood cell preparations, platelet preparations, plasma preparations, etc. The present invention relates to a filter priming method.

  It is becoming common for whole blood collected from a donor to be separated into blood component preparations such as erythrocyte preparations, platelet preparations, plasma preparations, etc., stored, and then transfused. In addition, since microaggregates and leukocytes contained in these blood products cause various side effects of blood transfusion, there are increasing opportunities for transfusion after removing these undesirable components before blood transfusion. In recent years, the need for leukocyte removal has been widely recognized, and an increasing number of countries have legislated that all blood products for blood transfusion are subjected to leukocyte removal treatment and then used for blood transfusion.

  The most common method for removing leukocytes from a blood product is to treat the blood product with a leukocyte removal filter. The treatment of blood products by this leukocyte removal filter was often performed at the bedside when performing a blood transfusion operation, but in recent years for the purpose of quality control of leukocyte removal products and the improvement of the effectiveness of leukocyte removal processing, It is common in developed countries to be done at the blood center before storage. Hereinafter, leukocyte removal performed before storage is referred to as “pre-storage leukocyte removal”.

  To collect blood from a donor, separate into multiple blood components, and store each blood component, typically two to four flexible bags and conduits connecting them, anticoagulant, red blood cell preservation solution Blood collection sets that consist of blood collection needles, etc. have been used for some time, but a system that incorporates a leukocyte removal filter into these blood collection sets that can be suitably used for the above-mentioned “leukocyte removal before storage” Is widely used, and is called by a name such as “closed system” or “integrated system”. These are disclosed in JP-A-1-320064, WO92 / 020428, etc.

  Conventionally, leukocyte removal filters in which a filter element made of a nonwoven fabric or a porous material is filled in a hard container such as polycarbonate have been widely used. However, the rigid container has a problem that it is difficult to apply steam sterilization, which is widely used as a sterilization process of a blood collection / separation set, because the gas permeability of the container is low. In the closed system, the whole blood product is first subjected to leukocyte removal after blood collection, the leukocyte removal filter is cut off, and then the centrifugation operation for component separation is performed, and the whole blood is separated into multiple blood components by centrifugation. In some cases, leukocyte removal is performed later. In the latter case, the leukocyte removal filter is also centrifuged together with the blood collection set. At this time, there is a possibility that the hard container may damage the bag or the conduit, or the hard container itself may be damaged without being able to withstand the stress during centrifugation.

  As a method for solving these problems, a flexible leukocyte removal filter using a flexible and vapor-permeable material that is the same as or similar to that used for a bag of a blood collection separation set. In fact, a product in which a flexible container is directly welded to a filter element (see JP-A-7-267871, WO95 / 017236 pamphlet) is known. In this type of conventional blood processing filter, for example, a flexible container is formed of a flexible sheet-like material, and the inner space of the flexible container is divided into one side and the other side by a filter element. It is divided into. And the port used as the entrance / exit of the blood is provided in the one side and other side divided by the filter element, respectively.

JP-A-01-320064 International Publication No. 92/020428 Pamphlet Japanese Patent Application Laid-Open No. 07-267871 International Publication No. 95/017236 Pamphlet

  However, in the conventional leukocyte removal filter, one side and the other side of the flexible container partitioned by the filter element often have substantially the same shape or the same volume. It cannot be said that sufficient studies have been made on filter performance related to suppression of blockage of filter elements derived from the mutual relationship with the side or prevention of air block generation during priming.

  An object of the present invention is to provide a blood treatment filter capable of improving filter performance.

That is, the present invention relates to a method for priming a blood treatment filter comprising a sheet-like filter element and a flexible container having an internal space partitioned on one side and the other side by the filter element. In particular, the flexible container of the blood treatment filter used in this priming method is provided in the first container forming part, the second container forming part, and the first container forming part, which are arranged to face each other with the filter element interposed therebetween. In addition, an inlet port serving as a blood inlet, an outlet port provided in the second container forming portion and serving as a blood outlet, and the first container forming portion and the filter element are sealed in a band shape so as to surround the inlet port. The formed annular first seal part, and at least the first container forming part and the second container forming part are sealed, and the annular is formed so as to surround the first seal part along the outer edge of the second container forming part The first container forming part has an inner filtration space forming part and an outer surrounding space forming part partitioned by the first seal part, and the second container forming part is And surrounded by the second seal part, The filter element and the expansion space forming portion disposed to face the surrounding space forming portion without being defined by one seal portion, and the inlet port is provided in the filtration space forming portion and defined by the filter element The outlet port communicates with the internal space on one side, communicates with the internal space on the other side provided in the expansion space forming portion and defined by the filter element, and protrudes from the outer surface of the expansion space forming portion. . Then, the priming method includes a step of setting the blood processing filter on the mounting surface in a state where the blood processing filter is laid sideways with the outlet port facing downward and inclined with respect to the mounting surface, A priming method for a blood treatment filter, comprising: a step of filling a chemical solution from a set outlet port of the blood treatment filter and evacuating the blood treatment filter. The blood in the present invention includes blood products such as whole blood preparations for blood transfusion, erythrocyte preparations, platelet preparations and plasma preparations.

In this blood processing filter priming method, the portion surrounded by the first seal portion of the filter element functions as an effective filtration portion of the filter element. Of the internal space of the flexible container, the space on one side is substantially a narrow space facing the effective filtration portion, and the space on the other side is not only the narrow space facing the effective filtration portion, but also the surrounding space. It becomes a wide space including an expanded space. Therefore, when the blood treatment filter is used so that this wide space side becomes the blood outlet side, for example, it is possible to prevent bubbles from accumulating on the surface on the outlet side of the filter element during priming to generate an air block. , Ru can improve filter performance. When priming the blood processing filter, the blood processing filter is set on the mounting surface with the outlet side facing downward. Since the blood treatment filter has an outlet port that protrudes from the outer surface of the expansion space forming portion, when the outlet side is set downward, the outlet port interferes with the mounting surface, and the blood treatment filter is inclined. It becomes a state. As a result, a part of the surrounding space forming portion that surrounds the filtering space forming portion in an annular shape is above the filtering space forming portion. Next, the drug solution is filled from the outlet port of the blood processing filter. Then, the interface of the chemical liquid rises with the filling of the chemical liquid. As a result, the air on the outlet side passes through the filter element and is pushed out from the inlet port. Here, some air remains in the space on the outlet side of the filter element. However, since there is a space for air accumulation formed by the surrounding space forming portion above the outlet side, the residual air escapes into the space for air accumulation, and the space on the outlet side corresponding to the filtration space forming portion. The air block inside can be suppressed and smooth air venting becomes possible.

In the priming method for the blood treatment filter, the outlet port may be disposed in a region of the expansion space forming portion that overlaps the filtration space forming portion.

In the priming method for the blood processing filter, the inlet port and the outlet port may be point-symmetric.

  According to the present invention, it is possible to improve the filter performance.

FIG. 1 is a plan view showing a part of the blood processing filter according to the first embodiment of the present invention in a cutaway manner. FIG. 2 is a cross-sectional view taken along the line II-II in FIG. FIG. 3 is a cross-sectional view taken along line III-III in FIG. FIG. 4 is a front view showing an outline of a blood processing system including the blood processing filter according to the first embodiment. FIG. 5 is a cross-sectional view showing a state where the blood processing filter according to the first embodiment is retro-primed. FIG. 6 is a diagram schematically showing a procedure for performing retro-priming on the blood treatment filter and then performing filtration treatment. (A) is a state in the middle of performing retro-priming, and (b) is a retro-process. FIG. 4C is a diagram illustrating an initial state in which priming has been completed, and FIG. FIG. 7 is a reference example of a blood processing filter, and is a cross-sectional view showing a state in which retropriming is performed on the blood processing filter according to the reference example. FIG. 8 is a cross-sectional view of a blood treatment filter according to the second embodiment. FIG. 9 is a cross-sectional view of a blood treatment filter according to the third embodiment. FIG. 10 is a cross-sectional view of a blood treatment filter according to the fourth embodiment.

  Embodiments of the present invention will be described below with reference to the drawings. The blood described in the following embodiments includes blood products such as whole blood products for transfusion, erythrocyte products, platelet products, and plasma products. In addition, the outer shape of the blood treatment filter can adopt various forms such as a rectangular shape, a disc shape, an oblong disc shape, and an elliptical shape, but a rectangular shape is preferable in order to reduce material loss during manufacturing. In the embodiment, a rectangular shape will be described as an example.

  First, the blood processing filter 1A according to the first embodiment will be described with reference to FIG. 1, FIG. 2, and FIG. The blood treatment filter 1A is a sheet-like container disposed so as to divide a flexible container 3 having a blood inlet port 9a and an outlet port 11a, and an inner space of the flexible container 3 into one side and the other side. And a filter element 5. The inlet port 9a communicates with the internal space on one side of the flexible container 3 defined by the filter element 5, and the outlet port 11a communicates with the internal space on the other side. In addition, the inlet port 9a and the outlet port 11a are arranged so as to be symmetric with respect to the virtual point X when the approximate center of the filter element 5 is determined as the virtual point X.

  The flexible container 3 is a rectangular flat container. The flat shape is intended to be a shape with a small thickness and a wide surface. The flexible container 3 includes a rectangular sheet-shaped first container forming part 9 and a rectangular sheet-shaped second container forming part 11, and the first container forming part 9 and the second container forming part 11 are filters. Opposing to each other with the element 5 interposed therebetween.

  The first container forming part 9 is sealed with an inlet port 9a in which an inlet channel 9b that communicates the inside and the outside is formed. The inlet port 9 a is an inlet that receives blood before processing into the internal space of the flexible container 3. The second container forming portion 11 is sealed with an outlet port 11a in which an outlet channel 11b that communicates the inside and the outside is formed. The outlet port 11a is an outlet for discharging the processed blood from the flexible container 3. Note that sealing means fixing by adhesion (including welding) to the extent that leakage of liquid can be prevented.

  The first container forming portion 9 is sealed along the periphery of the filter element 5 while being in close contact with the filter element 5. A portion sealed in a band shape along the periphery of the filter element 5 is an inner seal portion 13, and the inner seal portion 13 surrounds the inlet port 9 a in a rectangular ring shape.

  The first container forming part 9 is divided into an inner side surrounded by the inner seal part 13 and an outer side surrounding the inner seal part 13, and a portion inside the inner seal part 13 is a filtration space forming part 91. is there. The filtration space forming part 91 is provided with an inlet port 9a. Between the filtration space forming part 91 and the filter element 5, a filtration space S1 in which blood flowing from the inlet port 9a flows is formed. A part of the filter element 5 facing the filtration space S1 becomes an effective filtration part 5a. The inner seal portion 13 corresponds to a first seal portion. A protruding non-woven fabric portion 5c, which is an excess portion of the filter element 5, protrudes outside the inner seal portion 13.

  The peripheral edge of the first container forming portion 9 overlaps the peripheral edge of the second container forming portion 11 and is in close contact with each other and sealed in a band shape. The part sealed along the periphery of the first container forming part 9 and the second container forming part 11 is an outer seal part 15 surrounding the inner seal part 13 in a rectangular ring shape. A substantially donut-shaped portion formed between the inner seal portion 13 and the outer seal portion 15 is a surrounding space forming portion 92. The outer seal portion 15 corresponds to a second seal portion.

  On the outlet side of the filter element 5, a rectangular annular recess is formed corresponding to the rectangular annular inner seal portion 13. This recess is formed by integrating the filter element 5 with the first container forming portion 9 in a state where the filter element 5 is compressed from both sides in accordance with the formation of the inner seal portion 13. This recess is a trough 6 provided on the outlet side of the filter element 5.

  The valley 6 will be described in more detail (see FIG. 2). The filter element 5 formed by laminating a plurality of nonwoven fabrics has a certain thickness, and the surface of the filter element 5 is flat in a state where sealing such as welding is not performed. For example, when both surfaces of the filter element 5 are sandwiched between PVC sheets with a PVC sheet, the welded portion is crushed and integrated, and the integrated portion becomes thinner than the original thickness of the filter element 5.

  In the filter element 5 according to the present embodiment, in order to form the inner seal portion 13, for example, a process for sealing such as high-frequency welding is performed using a predetermined mold, and as a result, the ring element is integrated into an annular shape. A spot is formed. Even after the processing for sealing is performed, the portions other than the integrated portion are generally flat throughout, but only the vicinity of the integrated portion is different. For example, when paying attention to the outlet side of the filter element 5, the integrated portion is the bottom portion 6a that is the most depressed, and the portions adjacent to the integrated portion are the slope portions 6b and 6c that rise almost vertically from the bottom portion 6a. . That is, the valley portion 6 includes a bottom portion 6 a overlapping the inner seal portion 13, an inner slope portion 6 b rising from the bottom portion 6 a toward the inner side of the inner seal portion 13, and an outer slope surface rising toward the outer side of the inner seal portion 13. Part 6c.

  The second container forming part 11 is integrated with the first container forming part 9 via the outer seal part 15, but is not adhered to the filter element 5, and in the stationary state, the filter element 5 It is in a state of being substantially separated from the valley 6. That is, the second container forming portion 11 is not partitioned by the inner seal portion 13, so that the portion facing the filter element 5 and the portion facing the surrounding space forming portion 92 of the first container forming portion 9 are continuous. It has the expansion space formation part 12 arrange | positioned.

  The expansion space forming portion 12 forms an outlet-side filtration space S2 with the filter element 5, and forms an air reservoir space S3 from which air escapes during priming with the surrounding space forming portion 92. There is no partition between the filtration space S2 on the outlet side and the air pool space S3, and they are in communication with each other.

  The outlet port 11 a is provided in the expansion space forming portion 12 of the second container forming portion 11, and further protrudes from the outer surface 12 a of the expansion space forming portion 12. In particular, the outlet port 11a according to the present embodiment is arranged in a region Ar of the expansion space forming portion 12 that overlaps the filtration space forming portion 91 of the first container forming portion 9.

  Next, each aspect of the material and shape of each element constituting the blood processing filter 1A will be described. As described above, the flexible container 3 is formed by the first container forming part 9 and the second container forming part 11. If the flexible resin used for the flexible container 3 is a material marketed as a sheet | seat or a film, it can be used. For example, soft polyvinyl chloride, polyurethane, ethylene-vinyl acetate copolymer, polyolefin such as polyethylene and polypropylene, styrene-butadiene-styrene copolymer hydrogenated product, styrene-isoprene-styrene copolymer or hydrogenated product thereof Suitable materials include thermoplastic elastomers such as products, and mixtures of thermoplastic elastomers and softeners such as polyolefin and ethylene-ethyl acrylate. Since contact with blood is considered, soft vinyl chloride, polyurethane, polyolefin, and thermoplastic elastomers based on these are preferably used as materials for medical products such as blood bags, and more preferably Soft vinyl chloride.

  In addition, as the flexible container 3, for example, a container described in JP-A-7-267871 or a container described in International Publication No. 95/017236 can be used.

  The filter element 5 is manufactured using a filter material made of a fibrous aggregate such as a nonwoven fabric or a woven fabric or a porous material such as a sponge. In addition, in the filter element 5 which concerns on this embodiment, in order to make blood easy to get wet to filter material, you may coat a hydrophilic polymer. Further, when the blood treatment filter 1A is used to remove leukocytes from blood, a filter material coated with a polymer may be used in order to make leukocytes easily adhere to the filter element 5.

  Next, a method for manufacturing the blood processing filter 1A according to this embodiment will be described. In this manufacturing method, for example, a first container forming portion 9 having an inlet port 9a sealed at a predetermined position, a second container forming portion 11 having an outlet port 11a sealed at a predetermined position, and a filter element 5 are prepared, and a filter is prepared. An installation process is performed in which the first container forming portion 9 and the second container forming portion 11 are arranged at predetermined positions so as to sandwich the element 5.

  After the installation process, without sealing the filter element 5 and the second container forming part 11, the first container forming part 9 and the filter element 5 are sealed in a band shape so as to surround the site where the inlet port 9a is formed. The first sealing step for forming the seal portion 13 and the peripheral edges of the first container forming portion 9 and the second container forming portion 11 so as to surround the inner seal portion 13 are band-shaped to form an annular outer seal portion (first A second sealing step for forming the second sealing portion 15.

  By the first sealing step, a strip-shaped valley portion 6 corresponding to the inner seal portion 13 is generated on the outlet side of the filter element 5, and the valley portion 6 causes a gap between the second container forming portion 11 and the filter element 5. A passage region Ps is formed. Further, the inner side surrounded by the passage region Ps becomes the filtration space S2 on the outlet side, and the outer side becomes the space S3 for storing air.

  The formation of the inner seal portion 13 in the first sealing step, that is, the sealing of the first container forming portion 9 and the filter element 5 can be performed using high-frequency welding, but is not limited thereto. Various bonding techniques such as ultrasonic welding and heat welding can be used.

  Further, the formation of the outer seal portion 15 in the second sealing step, that is, the sealing between the first container forming portion 9 and the second container forming portion 11 can be performed using high frequency welding, but is not limited thereto. Instead, various bonding techniques such as ultrasonic welding and heat welding can be used.

  In the above manufacturing method, the inlet port 9a is sealed in advance to the first container forming portion 9 and the outlet port 11a is sealed in advance to the second container forming portion 11; Sealing may be performed after the sealing portion 15 is formed, or may be performed in the middle thereof. Further, in order to seal the inlet port 9a as the blood inlet and the outlet port 11a as the outlet to the flexible container 3, not only high-frequency welding but also various bonding techniques such as thermal welding can be used. As materials for the inlet port 9 a and the outlet port 11 a, various conventionally known materials can be used as in the flexible container 3.

  In the above manufacturing method, the second container forming portion 11 is not integrated with the filter element 5 in the inner seal portion 13, that is, not sealed with the filter element 5. It is advantageous that the arrangement of the outlet port 11a in the step of sealing the outlet port 11a has a relatively high degree of freedom. That is, sealing the inlet port 9a and the outlet port 11a in the flexible container 3 forms the inner seal portion 13 and the outer seal portion 15 in a simple step, and is a container-welded blood processing filter 1A. Although the inner sealing part 13 does not seal the second container forming part 11, it is possible to give a further degree of freedom to the arrangement of the outlet port 11 a.

  Next, a blood processing system 100 configured to include the blood processing filter 1A will be described (see FIG. 4).

  The blood treatment filter 1A can be used for filtration using gravity. For example, the blood processing system 100 to which the blood processing filter 1A is applied includes a storage bag 101 that contains blood after blood collection, a blood processing filter 1A, and a collection bag 103 that accumulates blood after filtration. In the collection bag 103, a priming storage solution (chemical solution) is placed in advance. In the present embodiment, an example in which a storage solution (chemical solution) for priming is placed in the recovery bag 103 in advance will be described as an example. However, a storage solution bag different from the recovery bag 103 is disposed. Alternatively, priming may be performed by appropriately switching the flow path.

  The storage bag 101 and the inlet port 9a of the blood processing filter 1A are connected to each other by a conduit 102a such as a blood tube. The recovery bag 103 and the outlet port 11a of the blood processing filter 1A are connected to each other by a conduit 104a such as a blood tube. An opening / closing means 102b such as a roller clamp that opens and closes a flow path, a chamber 102c, and the like are attached to the upstream conduit 102a, and an inlet-side circuit 102 is formed by the conduit 102a, the opening / closing means 102b, the chamber 102c, and the like. . Further, the outlet side circuit 104 is formed by the downstream side conduit 104a and the like.

  Next, a method for priming blood processing filter 1A will be described with reference to FIGS. Before blood treatment for the purpose of removing white blood cells or the like is performed, it is necessary to remove air from the blood treatment filter 1A to wet the filter element 5, and for this reason, retropriming is performed.

  When retropriming is performed on the blood processing filter 1A, the blood processing filter 1A is set on the mounting surface 110a of the substantially horizontal gantry 110 with the outlet side facing downward. The blood processing filter 1A is provided with an outlet port 11a protruding from the outer surface 12a of the expansion space forming part 12 of the second container forming part 11. Therefore, when the blood processing filter 1A is set with the outlet side facing down, the outlet port 11a interferes with the placement surface 110a, and the blood processing filter 1A is inclined (see FIG. 5). As a result, a part of the surrounding space forming portion 92 that surrounds the filtering space forming portion 91 in an annular shape is above the filtering space forming portion 91.

  Next, the collection bag 103 is installed above the blood processing filter 1A, and the storage bag 101 is installed below the blood processing filter 1A (see FIGS. 6 (a) and 6 (b)), and the inlet side circuit 102 and the outlet side circuit 104 are opened. The collection bag 103 contains a storage solution (drug solution) for diluting the blood. When the collection bag 103 is placed at a position higher than the blood treatment filter 1A, the storage solution in the collection bag 103 becomes the conduit 104a. Passes through to the blood processing filter 1A, and further passes through the outlet port 11a to fill the outlet side filtration space S2 in the flexible container 3. As the storage solution is filled, the interface of the storage solution rises. As a result, the air in the flexible container 3 passes through the filter element 5 and is pushed out from the inlet port 9a to be vented.

  In the process in which air is pushed out from the inlet port 9 a, some air remains in the space on the outlet side of the filter element 5. However, since the air storage space S3 exists above the filtration space S2 on the outlet side, the residual air escapes into the air storage space S3 and suppresses air block in the filtration space S2 on the outlet side. And smooth air venting is possible.

  In particular, in the case of the blood processing filter 1 </ b> A according to the present embodiment, the outlet port 11 a is disposed in a region Ar that overlaps the filtration space forming portion 91. That is, the outlet port 11a is provided not at the periphery of the expansion space forming portion 12 but at a relatively close position to the center, and the inclination of the blood processing filter 1A is increased. Accordingly, the escape of the residual air is promoted, and the air block suppression and smooth air venting in the filtration space S2 on the outlet side are performed more efficiently.

  The storage solution pushes out the air in the flexible container 3, passes through the inlet port 9 a, flows out into the conduit 102 a, and finally reaches the storage bag 101. This completes the retropriming.

  After the end of retropriming, normal blood processing (filtration processing) for the purpose of removing white blood cells or the like is performed (see FIG. 6C). In the case of normal blood processing, the storage bag 101 containing the blood after blood collection is installed at a position about 50 cm higher than the blood processing filter 1A, and the collection bag 103 for storing the filtered blood is about 100 cm higher than the blood processing filter 1A. Install in a low position.

  Blood is filtered by opening the flow path of the blood processing system 100. During the filtration process (in use), a negative pressure is generated on the outlet side of the flexible container 3 of the blood processing filter 1A, and the second container forming portion 11 is bent and is in close contact with the filter element 5. However, a trough portion 6 is formed on the outlet side of the filter element 5, and the outer slope portion 6 c (the protruding nonwoven fabric portion 5 c) of the trough portion 6 interferes with the second container forming portion 11 to the filter element 5. May be partly restricted, and the passage region Ps formed by the valley 6 is maintained as a gap. As a result, the blood channel is difficult to block, and the blood channel is easily maintained stably on the outlet side of the blood processing filter 1A.

  Next, the operation and effect of the blood processing filter 1A according to the present embodiment will be described. In the case of the blood treatment filter 1 </ b> A, the portion surrounded by the inner seal portion 13 of the filter element 5 functions as the effective filtration portion 5 a of the filter element 5. The filtration space S1 on the inlet side of the flexible container 3 is substantially a narrow space facing the effective filtration portion 5a, but the space on the outlet side is only a narrow filtration space S1 facing the effective filtration portion 5a. In other words, it becomes a wide space including the expanded air reservoir space S3. And since this wide space side becomes the blood outlet side, it is possible to prevent bubbles from accumulating on the outlet side surface of the filter element 5 during priming, thereby improving the filter performance.

  The above effect will be described with reference to FIG. 5 and FIG. FIG. 5 is a cross-sectional view of a blood processing filter according to this embodiment, and FIG. 7 is a cross-sectional view of a blood processing filter according to a reference example. The blood processing filter 200 according to the reference example includes a sheet-like filter element 201 and a flexible container 202 whose internal space is divided into an inlet side and an outlet side by the filter element. The flexible container 202 includes a first container forming part 203 and a second container forming part 204 that are disposed to face each other with the filter element 201 interposed therebetween. The first container forming part 203 is provided with an inlet port 203a. The second container forming unit 204 is provided with an outlet port 204a.

  The first container forming part 203 and the second container forming part 204 are integrated with the filter element 201 by both the inner seal part 210 and the outer seal part 211. That is, unlike the second container forming unit 11 according to the present embodiment, the second container forming unit 204 according to the reference example clearly defines the filtration space S5 and the surrounding space S6 by the inner seal unit 210. .

  As shown in FIG. 7, when the blood treatment filter according to the reference example is retro-primed, the air remaining in the filtration space S5 on the outlet side may lose escape and cause an air block. On the other hand, in the case of the blood processing filter 1A according to the present embodiment, as shown in FIG. 5, the residual air escapes to the air accumulation space S3 removed from the effective filtration portion 5a of the filter element 5. Therefore, air bubbles can be prevented from being generated on the surface of the filter element 5 on the outlet side, and the filter performance can be improved.

  Moreover, since the blood processing filter 1A has a valley 6 that is partially depressed on the outlet side of the filter element 5, it has an advantage even during normal filtration. That is, since the trough 6 is formed around the effective filtration portion 5a, the blood flow from the filter element 5 to the trough 6 that is the blood flow path on the outlet side is not concentrated at one point. It will spread. Therefore, even if a double force is applied due to the positive pressure on the inlet side and the negative pressure on the outlet side during filtration, the flow is hindered by the close contact between the second container forming part 11 and the filter element 5, A reduction in filtration performance is avoided. As a result, it is advantageous for effective use of the entire filter element 5, and both a high filtration flow rate and a high filtration performance can be achieved.

  Next, a blood processing filter according to a second embodiment of the present invention will be described with reference to FIG. FIG. 8 is a cross-sectional view of a blood treatment filter according to the second embodiment of the present invention. Note that the blood processing filter 1B according to the second embodiment includes substantially the same elements and structures as the blood processing filter 1A according to the first embodiment. Accordingly, in the following description, the same elements and structures are denoted by the same reference numerals, detailed description thereof is omitted, and different elements and structures are mainly described.

  The blood processing filter 1B is disposed so as to partition the flexible container 3 having the blood inlet port 9a and the outlet port 11a and the inner space of the flexible container 3 into the inlet port 9a side and the outlet port 11a side. The sheet-like filter element 5 and a welding sheet 31A disposed on the outlet side of the filter element 5 corresponding to the position where the inner seal portion 13 is formed are provided. The flexible container 3 includes a rectangular sheet-shaped first container forming section 9 and a rectangular sheet-shaped second container forming section 11.

  The first container forming part 9 and the second container forming part 11 are overlapped with each other via a rectangular filter element 5. The first container forming portion 9, the filter element 5, and the welding sheet 31 </ b> A are sealed and integrated with each other, and as a result, a band-shaped inner seal portion 13 is formed along the periphery of the filter element 5. . A trough portion 6 is formed in the filter element 5 by the inner seal portion 13, and a passage region is provided between the trough portion 6 and the second container forming portion 11 in a state in which blood is flowing (state in use). Ps is formed.

  In the case of the blood processing filter 1B according to the present embodiment, the space on the outlet side becomes a wide space including not only the narrow filtration space S2 facing the effective filtration portion 5a but also the surrounding expanded air reservoir space S3. And since this wide space side becomes the blood outlet side, it is possible to prevent bubbles from accumulating on the outlet side surface of the filter element 5 during priming, thereby improving the filter performance.

  Further, at the time of filtration, even if a double force is applied by the positive pressure on the inlet side and the negative pressure on the outlet side, the flow is obstructed by the close contact between the second container forming portion 11 and the filter element 5. It is advantageous to effectively use the entire filter element 5, and it is possible to achieve both high filtration flow rate and high filtration performance.

  Next, a blood processing filter according to a third embodiment of the present invention will be described with reference to FIG. FIG. 9 is a cross-sectional view of a blood processing filter according to a third embodiment of the present invention, and shows a state in which the blood processing filter is vertically used for normal filtration processing. The substantial difference between the blood processing filter 1C according to the third embodiment and the blood processing filter 1A according to the first embodiment is that the inlet port and the outlet port are reversed. In the following description, The difference will be mainly described, and substantially the same elements and structures will be denoted by the same reference numerals and detailed description thereof will be omitted.

  The blood processing filter 1C is a sheet-like container disposed so as to partition the flexible container 3 having a blood inlet port 11d and an outlet port 9d, and the inner space of the flexible container 3 into one side and the other side. And a filter element 5.

  The flexible container 3 includes a rectangular sheet-shaped first container forming portion 9 and a rectangular sheet-shaped second container forming portion 11, and an outlet port 9 d is formed in the first container forming portion 9. An inlet port 11 d is formed in the container forming part 11. The first container forming part 9 and the second container forming part 11 are arranged to face each other with the filter element 5 interposed therebetween. The outlet port 9d communicates with the internal space on one side of the flexible container 3 partitioned by the filter element 5, and the inlet port 11d communicates with the internal space on the other side.

  The flexible container 3 seals the first container forming part 9 and the filter element 5 in a band shape, and forms an annular inner seal part formed so as to surround an outlet port 9d provided in the first container forming part 9 ( The first seal portion 13, the first container forming portion 9, and the second container forming portion 11 are sealed, and the annular shape is formed so as to surround the inner seal portion 13 along the outer edge of the second container forming portion 11. And an outer seal portion (second seal portion) 15.

  The first container forming part 9 has an inner filtration space forming part 91 and an outer surrounding space forming part 92 partitioned by the inner seal part 13, and the second container forming part 11 is surrounded by the outer seal part 15. In addition, the filter element 5 and the expansion space forming portion 12 disposed to face the surrounding space forming portion 92 are provided without being partitioned by the inner seal portion 13. Further, the inlet port 11 d of the second container forming portion 11 is provided in the expansion space forming portion 12 and protrudes from the outer surface 12 a of the expansion space forming portion 12.

  In the blood treatment filter 1 </ b> C, a portion surrounded by the inner seal portion 13 of the filter element 5 functions as an effective filtration portion 5 a of the filter element 5. The filtration space S11 on the outlet side of the flexible container 3 is substantially a narrow space facing the effective filtration portion 5a, but the space on the inlet side is only a narrow filtration space S12 facing the effective filtration portion 5a. In other words, it becomes a wide space including the surrounding surplus space S13. Since this wide space side becomes the blood inlet side, for example, even if aggregates or bubbles enter during filtration, the aggregates and bubbles escape to the surrounding surplus space S13 that is out of the effective filtration portion 5a, and the filter element 5 can be suppressed, and the filter performance can be improved.

  Therefore, for example, even when processing blood in which the generation of aggregates is a concern, such as when the blood is refrigerated for a certain period of time, a large space is formed on the inlet side, so that aggregates adhere to the filter element 5. This can reduce the possibility of blocking.

  Next, a blood treatment filter according to a fourth embodiment of the present invention will be described with reference to FIG. FIG. 10 is a cross-sectional view of a blood processing filter according to a fourth embodiment of the present invention, and shows a state in which the blood processing filter is vertically used for normal filtration processing. The blood processing filter 1D according to the fourth embodiment includes substantially the same elements and structures as the blood processing filter 1C according to the third embodiment. Accordingly, in the following description, the same elements and structures are denoted by the same reference numerals, detailed description thereof is omitted, and different elements and structures are mainly described.

  The blood processing filter 1 </ b> D includes a welding sheet 31 </ b> B disposed on the inlet side of the filter element 5 corresponding to the position where the inner seal portion 13 is formed.

  The first container forming part 9 and the second container forming part 11 are overlapped with each other via a rectangular filter element 5. The first container forming portion 9, the filter element 5, and the welding sheet 31 </ b> B are sealed and integrated with each other, and as a result, a band-shaped inner seal portion 13 is formed along the periphery of the filter element 5. . A trough portion 6 is formed in the filter element 5 by the inner seal portion 13, and a passage region is provided between the trough portion 6 and the second container forming portion 11 in a state in which blood is flowing (state in use). Ps is formed.

  In the blood treatment filter 1 </ b> D, a portion surrounded by the inner seal portion 13 of the filter element 5 functions as an effective filtration portion 5 a of the filter element 5. The filtration space S11 on the outlet side of the flexible container 3 is substantially a narrow space facing the effective filtration portion 5a, but the space on the inlet side is only a narrow filtration space S12 facing the effective filtration portion 5a. In other words, it becomes a wide space including the surrounding surplus space S13. Since this wide space side becomes the blood inlet side, for example, even if aggregates or bubbles enter during filtration, the aggregates and bubbles escape to the surrounding surplus space S13 that is out of the effective filtration portion 5a, and the filter element 5 can be suppressed, and the filter performance can be improved.

  Therefore, for example, even when processing blood in which the generation of aggregates is a concern, such as when the blood is refrigerated for a certain period of time, a large space is formed on the inlet side, so that aggregates adhere to the filter element 5. This can reduce the possibility of blocking.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited by an Example.

[Example 1]
Using a blood processing filter comprising a flexible container and a filter element having an inlet side container forming part (first container forming part) and an outlet side container forming part (second container forming part), the inlet The port was connected to the storage bag via a 50 cm long inlet side circuit. The outlet port of the filter was connected to a collection bag containing 100 mL of red blood cell preservation solution (SAG-M) via an outlet side circuit having a length of 100 cm. A tube made of soft vinyl chloride having an inner diameter of 2.9 mm and an outer diameter of 4.2 mm was used for the inlet side circuit and the outlet side circuit.

In producing the blood treatment filter, the vertical dimension inside the first seal part is 74 cm, the horizontal dimension is 57 cm, the effective filtration part is rectangular, the corner part is curved, and the effective filtration area is 42 × 10 ⁻⁴ ( m ² ). The filter element has an air permeability of 237.3 (cc / cm ² / sec), four pieces of polyester nonwoven fabric with a thickness of 0.2 mm, and an air permeability of 8.4 (cc / cm) from the inlet to the outlet when blood is filtered. ² / sec), 0.4 mm thick polyester non-woven fabric, air permeability 7.7 (cc / cm ² / sec), 0.20 mm thick polyester non-woven fabric 32, air permeability 8.4 (Cc / cm ² / sec), one polyester non-woven fabric with a thickness of 0.4 mm, air permeability 237.3 (cc / cm ² / sec), polyester non-woven fabric with a thickness of 0.2 mm in the order of four A laminate was used. The air permeability was measured by a method based on Japanese Industrial Standard JIS L-1096, 6.27.1A.

  The two ports serving as the inlet and the outlet were each sealed in separate container forming portions. One container forming part and a filter element are overlapped to form a first seal part, and then the other container forming part is arranged so as to sandwich the filter element, and the peripheral edges of both container forming parts are overlapped to form a second A seal was formed. At that time, the opening and opening of each port was sealed and assembled so as to be arranged at a location inside the 2.4 cm filtration part from the end of the rectangular short side part of the first seal part on the effective filtration part side. And the port provided in the container formation part welded to the filter element by the 1st seal part was made into the port on the inlet side, and it connected with the circuit (inlet side circuit) of the side connected to a storage bag. Moreover, the port on the opposite side was used as the port on the outlet side, and connected to the circuit (exit side circuit) connected to the collection bag.

  The collection bag was suspended so that the drop from the circuit connection part of the collection bag to the flat blood treatment filter was 50 cm, the blood treatment filter and the storage bag were placed on a table, and the filter was primed with a red blood cell preservation solution. . At this time, the port on the inlet side of the red blood cell preservation solution (the outlet side at the time of blood filtration) was placed on the lower side so as to contact the table.

  After the red blood cell preservation solution completely flowed, the storage bag containing the red blood cell preservation solution used for priming was replaced with another storage bag containing the liquid to be treated (blood substitute) with a sterile connection device. At this time, the circuit length was maintained without change.

  As a liquid to be treated (substitute for blood), 300 g of a polyvinylpyrrolidone (weight average molecular weight 360,000) aqueous solution prepared at a viscosity of 17 mPa · s (25 ° C.) and a pH of 3.8 was used at room temperature. The total drop from the storage bag to the collection bag was fixed at 150 cm. The collection bag was previously placed on an upper pan balance so that the change in weight could be confirmed, and the liquid to be treated was filtered by gravity.

  At this time, the time required from the start of flowing the liquid to be processed until all the liquid to be processed in the storage bag is discharged and the weight increase of the weight conversion of the liquid recovery bag after filtration stops, that is, all the liquid is filtered. The time required to do this was measured and taken as the total processing time (minutes). The same test was repeated 10 times.

[Comparative Example 1]
The same method as in Example 1 except that the first seal part is formed by sandwiching the filter element between the two container forming parts, and then the second seal part is formed by sandwiching the filter element between the two container forming parts. The filter was assembled and filtered.
The results of Example 1 and Comparative Example 1 are shown in Table 1.

[Example 2]
The port provided in the container forming part welded to the filter element in the first seal part was used as an outlet side port, and was connected to a circuit (exit side circuit) connected to the collection bag. Moreover, the port on the opposite side was used as the port on the inlet side, and connected to the circuit (inlet side circuit) on the side connected to the storage bag. Further, the assembly of the blood treatment filter, the inlet side container, and the outlet are performed in the same manner as in Example 1 except that the storage bag contains the liquid to be treated and the collection bag uses an empty container that does not contain the red blood cell preservation solution. Connection to the side container was made.

  The total drop from the storage bag to the collection bag was fixed at 150 cm. The collection bag was previously placed on an upper pan balance so that the change in weight could be confirmed, and the liquid to be treated was filtered by gravity.

  The liquid to be treated was prepared by adding 70 mL of an anticoagulant solution (CPD-A) to 500 mL of pig whole blood and mixing it, and then storing it at 4 ° C. for 3 days in a flexible container. After taking out from the cool box, the blood cell component and the liquid component separated during storage were mixed by inversion and then immediately filtered.

  At this time, the time required from the start of flowing the liquid to be processed until all the liquid to be processed in the storage bag is discharged and the weight increase of the weight conversion of the liquid recovery bag after filtration stops, that is, all the liquid is filtered. The time required to do this was measured and taken as the total processing time (minutes). The same test was repeated 10 times.

[Comparative Example 2]
In the same manner as in Example 2, except that the first seal portion is formed by sandwiching the filter element between the two container forming portions, and then the second seal portion is formed by sandwiching the filter element between the two container forming portions. The filter was assembled and filtered.
The results of Example 2 and Comparative Example 2 are shown in Table 2.

  1A, 1B, 1C, 1D ... blood processing filter, 3 ... flexible container, 5 ... filter element, 9 ... first container forming part, 11 ... second container forming part, 9a, 11d ... inlet port, 11a, 9d DESCRIPTION OF SYMBOLS ... Outlet port, 12 ... Expansion space formation part, 13 ... Inner seal part (first seal part), 15 ... Outer seal part (second seal part), 91 ... Filtration space formation part, 92 ... Ambient space formation part

Claims (3)

A priming method for a blood treatment filter comprising a sheet-like filter element and a flexible container having an internal space partitioned on one side and the other side by the filter element,
The flexible container includes a first container forming portion and a second container forming portion disposed to face each other with the filter element interposed therebetween, and an inlet port provided in the first container forming portion and serving as an inlet for blood. An annular outlet port provided in the second container forming portion and serving as a blood outlet, sealing the first container forming portion and the filter element in a band shape and surrounding the inlet port. An annular ring formed so as to seal the first seal portion, at least the first container forming portion, and the second container forming portion, and surround the first seal portion along the outer edge of the second container forming portion. A second seal portion,
The first container forming portion has an inner filtration space forming portion and an outer surrounding space forming portion partitioned by the first seal portion, and the second container forming portion is surrounded by the second seal portion. And having an expanded space forming portion disposed to face the filter element and the surrounding space forming portion without being partitioned by the first seal portion,
The inlet port is provided in the filtration space forming portion and communicates with an internal space on one side partitioned by the filter element, and the outlet port is provided in the expansion space forming portion and by the filter element. It communicates with the partitioned inner space and protrudes from the outer surface of the expansion space forming portion. The blood treatment filter is placed sideways with the outlet port facing downward and inclined with respect to the mounting surface. Setting the blood treatment filter on the placement surface as described above,
A blood treatment filter priming method comprising: filling a chemical solution from the outlet port of the blood treatment filter set on the mounting surface, and evacuating the blood treatment filter. Said outlet port, said extension of the space forming part, the filtration space forming portion priming method of a blood treating filter according to claim 1, wherein disposed in the region overlapping the. Wherein the inlet port and the outlet port, according to claim 1 or 2 priming method of a blood treating filter according a point symmetry.

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